As is well known in the art, a plasma display device realizes a desired image using plasma discharge. Such a plasma display device generally includes a plasma display panel (PDP) for realizing the desired image through plasma discharge, which is activated by an external power source; a chassis base for firmly holding the PDP and for forming structural strength of a plasma display device; a driving circuit for driving the PDP; and a power supply circuit.
The driving circuit and the power supply circuit are mounted to the side opposite of the PDP on the chassis base. The side of the chassis base to which the PDP is mounted is called a front side, and the side of the chassis base to which the circuits are mounted is called a rear side.
The driving circuit and the power supply circuit, which include a plurality of circuital elements such as a resistor, a capacitor, and an integrated circuit (IC), are usually manufactured and mounted to the chassis base in the form of a printed circuit board (PCB).
FIG. 1 illustrates how a PCB is mounted to a chassis base according to the prior art.
As shown in FIG. 1, a plurality of mounting bosses 110 are formed at a rear side of chassis base 100, for mounting of PCB 150. Mounting holes 160 are formed at PCB 150 for engagement with mounting bosses 110. Screw fasteners 162 are engaged with bosses 110 through mounting holes 160 while mounting bosses 110 and mounting holes 160 are aligned, so PCB 150 becomes firmly mounted to chassis base 100.
For the grounding of circuits, PCB 150 has grounding holes 170 separate from mounting holes 160. Grounding bosses 120 corresponding to grounding holes 170 are formed at chassis base 100 and become tightly fitted to grounding holes 170. A copper land 172 is formed around grounding hole 170 of PCB 150, so the circuit on PCB 150 may be grounded through grounding boss 120.
According to a plasma display device of the prior art, production efficiency of a plasma display device may be deteriorated and production cost may be increased because numerous bosses including bosses 110 for mounting PCB 150 have to be formed at chassis base 100. Furthermore, mounting of PCB 150 to chassis base 100 is only enabled by screw-engaging many screw fasteners to the bosses.
Also according to a plasma display device of the prior art, PCB 150 is grounded through a few contact points between PCB 150 and chassis base 100, wherein connection between the contact points depends on contact between grounding bosses 120 and copper land 172 of grounding holes 170. Therefore, if the contact area between PCB 150 and chassis base 100 is increased, the grounding effect of PCB 150 may be enhanced and electromagnetic interference (EMI) by circuits of PCB 150 may be better shielded.
Because a chassis base must provide sufficient strength, research has been conducted to search for ways to strengthen the chassis base. An example of such research is found in Laid Open Japanese Patent publication 2002-099218 (filing no.: 2000-288523).
If the strength of a chassis base is enhanced the mechanical reliability of a plasma display device becomes efficiently enhanced.